In this paper, a two-species diffusive predator-prey model with time delay and functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, t...In this paper, a two-species diffusive predator-prey model with time delay and functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established.展开更多
By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for a nonautonomous diffusive food chain system of three species.is established, where ri(t), aii(t) (i = 1...By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for a nonautonomous diffusive food chain system of three species.is established, where ri(t), aii(t) (i = 1.2,3,4), Di(t) (i = 1,2), a12(t), a21(t), a23(t) and a32(t) are all positive periodic continuous functions with period w > 0, Ti(i = 1,2) are positive constants.展开更多
We obtain sufficient condition for the existence of periodic solutions of thefollowing second order functional differential equationsx'(t) + ax'~α(t) + bf(x(t)) + g(x(t-T_1), x'(t-T_2))=p(t)=p(t+2π).Our ...We obtain sufficient condition for the existence of periodic solutions of thefollowing second order functional differential equationsx'(t) + ax'~α(t) + bf(x(t)) + g(x(t-T_1), x'(t-T_2))=p(t)=p(t+2π).Our approach is based on the continuation theorem of coincidence degree, andthe α-priori: estimate of periodic solutions.展开更多
基金Research supported by the Major and Youth Project Foundation of Hubei Province Education Department(2001z06003)(200200002)
文摘In this paper, a two-species diffusive predator-prey model with time delay and functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established.
基金Supported by the National Natural Science Foundation of China (No.19971026,10271044).
文摘By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for a nonautonomous diffusive food chain system of three species.is established, where ri(t), aii(t) (i = 1.2,3,4), Di(t) (i = 1,2), a12(t), a21(t), a23(t) and a32(t) are all positive periodic continuous functions with period w > 0, Ti(i = 1,2) are positive constants.
基金The project is supported by NNSF of China(No.10271044)
文摘We obtain sufficient condition for the existence of periodic solutions of thefollowing second order functional differential equationsx'(t) + ax'~α(t) + bf(x(t)) + g(x(t-T_1), x'(t-T_2))=p(t)=p(t+2π).Our approach is based on the continuation theorem of coincidence degree, andthe α-priori: estimate of periodic solutions.